BQ28Z610-R1: BQ28Z610 – COV flag detected but Charge FET not turning OFF (OV cutoff issue)

Hello TI Team,

I am testing the BQ28Z610 fuel gauge IC on my custom PCB and I am facing an issue related to over-voltage cutoff (COV).

• The system is a 1-cell configuration.

• I have configured the Cell Over Voltage (COV) threshold using bqStudio.

• When the cell voltage crosses the configured COV threshold:

  • COV flag is set

  • TCA flag is set

  • XCHG flag is set

• However, the Charge FET does NOT turn OFF, and charging continues even though all the safety flags are correctly detected.

Observation

• Under-voltage cutoff (CUV) is working perfectly.

• Only the over-voltage cutoff is not disconnecting the Charge FET.

Additional Information

• On my PCB:

  • During charging, the current is shown as negative

  • During discharging, the current is shown as positive

• I am not sure if this current polarity issue could be related to the Charge FET not turning OFF during COV.

My Questions

1. Could this issue be caused by:

   • Incorrect software / data flash configuration, or

   • A hardware design issue (FET connection, sense resistor polarity, CHG/DSG FET orientation, etc.)?

2. Does the negative charging current indication affect COV behavior or FET control?

3. Are there any specific settings (FET options, safety settings, permanent failure settings, or recovery conditions) that could prevent the Charge FET from turning OFF even when COV is detected?

Attachments:
My_fuelgauage_data.gg.csv 

I would appreciate your guidance on what to check next to resolve this issue.

Thank you for your support.